1. Field Of The Invention
The invention is an Emergency Drug Injection and Circulatory Distribution Control Device (EDICDD) which can be used to administer drugs forcefully into circulatory decompensated human or animal patients.
2. Background Art
CPR is a general term that encompasses both basic life support (BLS), consisting of manual chest compression and ventilation, and advanced cardiac life support (ACLS), involving the more sophisticated techniques and technology utilized in CPR. Included within the domain of ACLS is drug therapy and considerations in drug administration.
Until recently, drug therapy standards for ACLS had developed empirically, with little supporting scientific data, despite their critical roles in resuscitation. Within the past several years, data has been obtained from both animal and clinical studies which challenge the adequacy of the traditional drug protocols, including those involving the routes of drug administration during cardiac arrest. See, Barsan, Hedges, Nishiyama and Lukes, Differences in Drug Delivery With Peripheral and Central Venous Injection. American Journal of Emergency Medicine. Vol. 4, No. 1, p.1, January 1986, hereinafter, Barsan, Hedges et al; Doan, Peripheral versus Central Venous Delivery of Medications during CPR, Annals of Emergency Medicine (Part 2) 13:784786, September 1984, hereinafter, Doan; Barsan, Levy and Weir, Lidocaine Levels During CPR: Differences After Peripheral Venous, Central Venous and Intracardiac Injections, Annals of Emergency Medicine 10:73-78, February 1981, hereinafter, Barsan, Levy, et al; Kuhn, White, Swetnam, Mumey, Rydesky, Tintinalli, Krome, and Hoehner, Peripheral versus Central Circulation Times During CPR: A Pilot Study, Annals of Emergency Medicine 10:417-419 August 1981, hereinafter Kuhn, et al; Hedges, Barsan, Doan, Joyce, Lukes, Dalsey and Nishiyama, Central Versus Peripheral Intravenous Routes in Cardiopulmonary Resuscitation, American Journal of Emergency Medicine, Vol. 2, No. 5, Page 385, September 1984, hereinafter, Hedges, et al; Keats, Jackson, Kosnick, Tworek and Zawanger, Effect of Peripheral Versus Central Injection of Epinephrine or Changes in Aortic Diastolic Pressure During Closed Chest Massage in Dogs, Annals of Emergency Medicine 14:495, May 1985, hereinafter. Keats et al.
In 1985, The National Conference on Standards and Guidelines for Cardiopulmonary Resuscitation (CPR) and Emergency Cardiac Care (ECC), sponsored by the American Heart Association, examined treatment guidelines for CPR that had been established by previous conferences. In light of scientific and clinical data available since 1979, the 1985 Conference substantially revised these guidelines, particularly in the areas of drug therapy and methods of administration. In 1986, all of the revised standards and guidelines from this conference were published in the Journal of the American Medical Association and have become the basis for current medical practice during ACLS. See, Standards for CPR & ECC Part III: Adult Cardiac Life Support, Journal of American Medical Assn., Vol 225, No. 21, Page 2933, June 6, 1986, hereinafter, Standards.
An essential component of ACLS is the early establishment of a reliable intravenous line for the administration of drugs and fluids. The 1985 Conference drew three important conclusions relative to this that have also been embraced by the American Heart Association:
1. Avoid intra-cardiac injection.
2. When available, always use a central venous catheter to inject drugs.
3. CPR is not to be interrupted for the insertion of a central venous catheter, therefore drugs may be administered via peripheral intravenous sites. In these instances, the drug injection is to be followed by the injection of a flush solution to facilitate drug entrance into the general circulation.
While current scientific data show that a central venous catheter is the superior route for drug administration during CPR, See, Kowenhoven, W. B., Jude, J. R., Knickerbocker, C. G., Closed-chest Cardiac Massage, JAMA 1960:173:1064-7; Raehl, Advances in Drug Therapy of Cardiopulmonary Arrest, Clinical Pharmacy, Vol. 6, February 1987, p. 118, hereinafter, Raehl; American Heart Associaton and National Academy of Sciences National Research Council: Standards and Guidelines For Cardiopulmonary Resusciation (CPR) and Emergency Cardiac Care (ECC), JAMA 1986: 255:2905-92; Barsan, Hedges, et al; Doan; Barsan, Levy, et al; Kuhn, et al; Hedges, et al; Keats, et al, in actuality, this route is frequently not possible, particularly in the non-institutional setting. Attempts at cannulating patients for central venous catheterization during CPR are not recommended due to the increase risk of inducing pneumothorax when the patient is being bounced by cardiac compressions. See, Schwartz, Principes & Practice of Emergency Medicine, 1986, hereinafter, Schwartz. Furthermore, such measures may require interruption of CPR at a stage when priority must be given to ventilation, oxygenation and chest compression. Therefore, if no central vein has been cannulated prior to the arrest, cannulation of the peripheral antecubital vein should be the site of first choice. Id.
Advantages of peripheral venous cannulation are that is easier, quicker, results in fewer complications, and does not require interruption of CPR. Since the majority of affected patients will initially require drug therapy using a peripheral vein, a method for achieving rapid and high blood concentrations of drug using the peripheral route has been outlined in the "Standards of CPR and ECC". The guidelines recommend using a large volume of flush solution following the injection of a drug in order to more rapidly distribute the drug into the central circulation. See, Standards. This system is considered equivalent to using a central venous catheter for drug administration. Unfortunately, this system also poses some problems in terms of safety and practicality. The flush solution (30-60 milliliters) needs to be injected immediately following drug administration. This requires that the flush solution be administered by a syringe that has been prepared just prior to administration, a labor and time intensive task. In addition, each time the flush solution is given, the closed sterile system needs to be entered (broken). These steps must be repeated numerous times during a cardiac arrest since a multiplicity of drugs are injected as frequently as every few minutes for as long as 20 to 40 minutes. With these points in mind, the disadvantages inherent to such an arrangement are as follows:
1. Critical time is lost since each new flush requires preparation and in insertion of an additional syringe.
2. The quantity of contaminated "dirty" needles created will raise the risks to health care providers of infectious disease exposure.
3. It will require an extra person in an already crowded situation to prepare flush solutions.
4. Confusion may occur as to whether or not a drug has been given since both drug and flush are colorless liquids.
5. The chance of introducing air embolus or bacteria (and subsequent infection) is increased each time the sterile system is broken for the extra flush solution.
6. The supplies needed, and thus cost and storage space for emergency cart supplies, are increased.
At the present there are no devices currently available designed to administer drugs forcefully into circulatory decompensated patients for example, during cardiopulmonary arrest. The Emergency Drug Injection and Circulatory Distribution Device (EDICDD) disclosed is designed to carry out this function. Although, many of the parts of the EDICDD are derived from already existing commercially available products, none of these products are designed to perform the vital functions of the EDICDD.
U.S. Pat. No. 2,866,456 (Moore) demonstrates a means of administering parenteral fluids into an intravenous tubing set-up. This device does not concern itself with drawing fluid from a reservoir aseptically or forcefully injecting drugs into circulation. U.S. Pat. No. 4,114,617 (Turner) is also designed to administer supplemental drugs (blood) into an already existing operational intravenous system. Turner used check valves, but these are of common nature and are found in other devices. Once again Turner's apparatus does not provide a mechanism by which drugs can be forcefully injected into a patient's circulation. Villari, U.S. Pat. No. 4,051,852 contains one-way check valves similar to those described in the EDICDD, but once again these are of common type and design, and this device by Villari is not intended to forcefully administer drugs into a patient's general circulation.
Kas, U.S. Pat. No. 2,825,334, deals with a check valve system similar to that used in the EDICDD, which are common devices utilized routinely. The recoil mechanism of Kas is similar to that of the EDICDD, but does not contain guiding rods, and is not designed maintain sterility after multiple injections (the plunger shaft). This device was designed to be used for livestock only.
The spike apparatus described in Kersten, U.S. Pat. No. 4,411,661, is similar to that of the EDICDD and is a common component of intravenous tubings found with many brands of tubings. This device is designed to allow fluid to flow from a fluid reservoir into intravenous tubing maintaining a closed system and sterility.
Kaiser, et al, U.S. Pat. No. 2,854,027, deals With a valve system providing similar actions as the EDICDD valve apparatus part 15, however, the mechanics of these two systems are different and not comparable. The art of Zeddies, et al., U.S. Pat. No. 4,005,710, deals with an injection port similar to the injection port numbered 55 of the EDICDD. Once again this injection port is a common device utilized on many types of intravenous tubing sets This injection port, with its one-way valve, allows for a drug to be injected into an intravenous tubing set while preventing a backflow of fluid/drug in the tubing, by way of the one-way valve. The device by Rudenza et al, U.S. Pat. No. 4,504,265, primarily concerns administering a bolus of medication quickly when upstream flow of an intravenous fluid is slow and may delay delivery of the medication. It is of a controlled rate and not designed to deliver medications during cardiopulmonary arrest and circulatory collapse in critical situations. The piston/syringe mechanism of Rudenza et al does not involve one-way valves, and the syringe with fluid needs to be inserted into the piston with each injection. Villancort, U.S. Pat. No. 4,585,435 deals with an extension set designed to allow administration of two different drugs/fluids simultaneously. This device does not contain valves or a syringe/plunger apparatus for rapid delivery of drugs into a patient's circulation under critical conditions.
Two patents by Raines, U.S. Pat. No. 4,244,366 and No. 4,246,932 deal with a syringe stroke controlling device and a multiple additive valve assembly, respectively. These two devices are used together in an apparatus for aspirating fluid from a container into a calibrated syringe. Adjustable guiding pins are utilized in order to control the volume of fluid in the syringe. The syringe used is 10 ml. in volume and, if used repeatedly for many aspirations and pumping, must be contained in a sterile environment in order to maintain its sterility. The EDICDD contains a 60 ml syringe with a nonadjustable internal volume of 25 ml designed to help maintain sterility after multiple injections and recoil. The recoil mechanisms of Raines and the EDICDD are similar. However, that of the EDICDD is designed for a 25 ml. volume and is covered to enable maintaining sterility during use in an open environment. This covered plunger shaft/recoil mechanism protects the EDICDD from spilled blood, fluids, and user touch contamination. The EDICDD, in addition, contains tubing and an injection port for the administration of other drugs/fluids. The valves on the EDICDD need not be specifically similar to those of Raines, but can be of any type of construction.